In cells such as chlorate cells for the production of chlorate by the electrolysis of brine, it has been known to use coated titanium anodes. The anodes can comprise a plurality of spaced-apart members and the members can be positioned side-by-side in parallel rows. The anode members can be connected together and such connections can be by members taking different forms such as ribs and base plates. These connecting members, which may be positioned in a manner transverse to parallel rows of anodes may serve as current distributors for impressing an electrical current onto the anode members.
It has been known that the titanium anodes may carry a coating, such as an electrocatalytic coating of a platinum group metal oxide, with the anodes being in the form of plates. For example, British Patent No. 1,076,973 discloses titanium plate anodes, which plate anodes are in parallel rows, side-by-side and spaced apart one from the other. The plate anodes can have an electrocatalytic coating and, as shown in the patent, a transverse rib member serving as a current distributor or busbar.
U.S. Pat. No. 4,022,679 discloses titanium described in the form of bands or strips which are coated and serve as anodes. The bands or strips run parallel to one another and are spaced apart from each other. Current is distributed to these parallel rows of titanium strips by a transverse bar of uncoated titanium which is welded to the strips.
For distributing current to the electrodes, the distributor may be in the form of a sheet or a plate, sometimes referred to as the base plate of the cell. U.S. Pat. No. 4,078,986 shows a titanium sheet serving as a base plate of a cell. To the base plate, there are welded parallel rows of support ribs and from these ribs there extend anodes in sheet form. These anodes may be fabricated of titanium and provided with an electrocatalytically active coating. The sheet anodes are welded to the ribs.
In these various constructions when it is time to recoat the anodes, it has been conventional to remove the plate anodes from the cell, including cutting the plate anodes from a base plate. The anodes can then have the old coating removed by vigorous processing which may include abrasive blasting of the anode surfaces. Thereafter, a fresh coating is applied to the anode plates and then they are reinstalled in the cell, e.g., by welding again to the base plate.
It would be highly desirable to have a more expedient manner of refurbishing used electrodes. It would also be most desirable if such innovation could improve turn around time to reduce plant outages.